package com.itheima.reggie.Filter;

import com.alibaba.fastjson.JSON;
import com.itheima.reggie.Common.BaseContext;
import com.itheima.reggie.Common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 检查用户是否已经完成登录的过滤器
 */
@WebFilter(filterName = "LoginCheckFilter",urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {
   //匹配器
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

         // 1.获取本次请求的urI
        String requestURI = request.getRequestURI();//backend/index.html无法通过进行**通配符匹配
        //定义不需要处理的请求路径
        log.info("拦截到请求：{}",requestURI);
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/user/sendMsg",
                "/common/**",
                "/user/login"


        };
         // 2.判断本次请求是否需要处理
        boolean check = check(urls,requestURI);

        //3.不需要处理，直接放行
        if(check){
            log.info("本次请求{}不需要处理",requestURI);
            filterChain.doFilter(request,response);
            return;
        }

         // 4.判断登录状态，如果已经登录，直接放行
        if(request.getSession().getAttribute("employee")!=null){
            log.info("用户已登录,用户id为:{}",request.getSession().getAttribute("employee"));
            Long empId = (Long)request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(empId);
            filterChain.doFilter(request,response);
            return;
        }

        // 4-2.判断登录状态，如果已经登录，直接放行
        if(request.getSession().getAttribute("user")!=null){
            log.info("用户已登录,用户id为:{}",request.getSession().getAttribute("user"));
            Long userId = (Long)request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);
            filterChain.doFilter(request,response);
            return;
        }


        log.info("用户未登录");
        // 5.如果未登录则返回未登录结果,通过客户端输出方式来返回页面的响应数据
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;
    }



    /**
     * 检查本次请求是否需要放行
     * @param urls
     * @param requestURI
     * @return
     */
    public boolean check(String [] urls,String requestURI){
        for(String url : urls){
            boolean match = PATH_MATCHER.match(url, requestURI);
            if(match){
                return true;
            }
        }
        return false;
    }
}
